#version 450
#extension GL_ARB_separate_shader_objects : enable

out gl_PerVertex {
   vec4 gl_Position;
};

vec2 positions[3] = vec2[](
   vec2( 0.0, -0.5),
   vec2( 0.5,  0.5),
   vec2(-0.5,  0.5)
);

vec3 colors[3] = vec3[] (
   vec3(1.0, 0.0, 0.0),
   vec3(0.0, 1.0, 0.0),
   vec3(0.0, 0.0, 1.0)
);

layout(location = 0) out vec3 color;

void main() {
   gl_Position = vec4(positions[gl_VertexIndex], 0.0, 1.0);
   color = colors[gl_VertexIndex];
}
